Rice Lake LCP-1 User Manual

LCP-1 Load Cell Transient Protection System

Technical Card

Product Information

The LCP-1 is a DC Transient protection system for strain gauge load cells and for RS-232C serial data
lines. You can use it with 175 Ω , 350 Ω , 700 Ω , or 1,000 Ω impedance cells.

The maximum excitation voltage (measured from [+] Excitation to [-] Excitation) is 20 VDC. It will
work with AC or “chopped” supplies as long as the peak to peak signal doesn’t exceed approximately 9
VDC. LCP-1 is for four wire systems only. For installations requiring extensive remote sensing, use the
LCP-2 with remote sense protection.

Environment

LCP-1 is designed to go in NEMA 1,2,3, or 11 environments. This means indoors in damp or dusty
environments, or outdoors in wet environments like you would get from rain or dew. It is not designed
for NEMA 4X or 6 areas where the box will be sprayed with a fire hose or be under water. If the LCP-1
must be submerged or hosed down, use Perm-a-tex Number 2 removable gasket compound on both
sides of the gasket (install in the field). This provides an excellent seal which will not leak under the
worst conditions. The LCP-1 will work well in most pit environments or outdoors. LCP-1 units are
potted except for the connectors. If the inside should get wet, simply dry them out with air or alcohol.
Internal damage is very unlikely. If moisture tends to accumulate in the enclosure, install a small silica
gel or other dessicant bag in the enclosure. If you do, remember to change it about every six months.

Mounting

Pick a mounting site near the cell you wish to protect. If this is in a pit, mount the LCP-1 as high up on
the steel as possible (this helps in the rainy season). If water is a real problem, mount the unit upside
down. Use stainless steel or monel hardware for mounting whenever possible.

December 2000 66951